Arc-light electrode.



' To all whom it may concern:

UNITED STATES PATENT OFFICE.

EMILE J. GUAY, or LYNN, MASSACHUSETTS, ASSIGNOR T GENERAL ELECTRIC COMPANY, A CORPORATION on NEW YORK.

ABC-LIGHT ELECTRODE. I

No Drawing.

Specification of Letters Yatent.

Be it known that I, EMILE J. GUAY, a citizen of the United States, residing at Lvnn, in the county of Essex, State of Massachusetts, have invented certain new and useful Improvements in Arc-Light Electrodes, of which the following is a specification.

My invention has reference to an electrode of the flaming or luminous type, in which the chief light giving constituent is titanium oarbid or other titanium compound.

In flaming or luminous arcs, as is well known, most of the light is emitted the:

ing point is high, higher in fact than the light giving constituent by incorporating a steady vaporizing point, withthe consequence that the arc springs from' a small spot which jumps about irregularly on the arcing surface of the elect-rode, driving the arc in different directions and thus producing an unsteadiness in the arc. This movement of the arc is at times so rapid that the arc collapses altogether and causes a premature feeding operation of the lamp. This unsteadiness of the arc is accentuated by the fact that a titanium carbid arc is long and thin and runs at a high temperature. I have.

overcome this unsteady tendency in an arc in which tltanlum carbid 1s the principal with the titanium carbid other materials which form a pool relatively larger than the spot from which the titanium carbid arc springs, and at the same time fattens or enlarges the arc, both of which features exert influence thereon. y

speclfically my electrode is composed of titanium carbid, cerium fluorid, cerium tungstate, cryolite and carbon. The cryolite possesses a low melting point and a high boiling point and formsa liquid pool on the tip of the electrode into which the other constituents of the electrode enter'and from which their vapors pass into the arc. Of course these constituents, the cerium fiuorid makes the arc larger and cooler than and carbon 35%.

a fairly eflicientlight producing material. This constituent 1s not, however, suitable for the purposes of my invention in the absence of the cryolite, since in that case it would volatlllze in the electrode before it enters into the .arc. The'cerium tungstate gives a otherwise have. Carbon is added to the electrode to give conductivity to the-pool in v its congealed condition. -In the absence of the carbon, difliculty is at times experienced in striking the varc, as the pool containing the constituents of the elect-rode other than carbon is non-conducting when cold and thus the arc is not always properly established on separation of the electrodes. The carbon becomes disseminated in theliquid pool and gives conductivity thereto even when it is cool, thus insuring the proper establishment of the are on the separation of the electrodes. The carbon is also valuable in giving conductivity to the electrode itself.

An electrode made in accordance with the above description gives a very efiicient white light. In case a yellow light is desired, the ceriumtungstate may be'dispensed with, but in that case a larger proportion of cryolite is necessary, for instance 12, or 15 parts, whereas about 5 parts are sufficient in the first case.

' I have made an excellent electrodeby making a paste of the constituents, squirting the same and baking the sticks thus formed. The electrode thus formed may be coated with carbon by painting with tar or any suitable carbonizable material. I havealso made a good electrode by squirting the constituents into a carbon shell. It will be understood, however, that the particular method of making the electrode forms no part of my invention.

I have made an excellent electrode with Patented Sept. 24., 1912. Application filed May 22, 191 1. Serial No. 628,634. 4

a titanium carbid arc'and is'at the same time the constituents in the following proportions: titanium carbid 25%; cerium fluorid 20%; cerium tungstate 15%; cryolite 5%; These constituents may, however, be varied and still produce a useful and efficient electrode. stance, good electrodes result from the use of titanium carbid from 20 to30 parts;

cerium fluorid 15 to 25 parts; cerium tung- 1 Thus, for in-' state from 12 to 18 parts; carbon 80 to 35 parts; cryolite 5 parts. The cryolite should not vary substantially from the percentage above indicated.

While I have described my invention as particularly applicable to an electrode in which titanium carbid is present, it is to be understood that I am not limited to titanium carbid, as I have found that titanium sub oxid together with the other constituents produces an excellent electrode.

What I c1a1m as new and deslre to secure by Letters Patent of the United States, is

i oeaeee fluorid 15 to 25 parts; cerium tungstate li l to 18 parts; eryolite substantially 5 parts; carbon 30 to 35 parts.

3. An are light electrode composed of the following constituents in substantially the proportions indicated: titanium cal-bid 25% cerium fiuorid 20%; cerium tungstate 15%; cryolite 5%; carbon 35%.

4. An are light electrode containing a titanium compound, cerium fluorid, cryolite and carbon.

5. An arc electrode containingtitanium I carbid, cerium fiuorid, cryolite and carbon. In Witness whereof I have hereunto set ,my hand this 18th day of May, 1911.

EMILE J. GUAY. 

